drivers/gpio/gpio-da9055.c

   1 /*
   2  * GPIO Driver for Dialog DA9055 PMICs.
   3  *
   4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
   5  *
   6  * Author: David Dajun Chen <dchen@diasemi.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/gpio.h>
  17
  18 #include <linux/mfd/da9055/core.h>
  19 #include <linux/mfd/da9055/reg.h>
  20 #include <linux/mfd/da9055/pdata.h>
  21
  22 #define DA9055_VDD_IO                   0x0
  23 #define DA9055_PUSH_PULL                0x3
  24 #define DA9055_ACT_LOW                  0x0
  25 #define DA9055_GPI                      0x1
  26 #define DA9055_PORT_MASK                0x3
  27 #define DA9055_PORT_SHIFT(offset)       (4 * (offset % 2))
  28
  29 #define DA9055_INPUT                    DA9055_GPI
  30 #define DA9055_OUTPUT                   DA9055_PUSH_PULL
  31 #define DA9055_IRQ_GPI0                 3
  32
  33 struct da9055_gpio {
  34         struct da9055 *da9055;
  35         struct gpio_chip gp;
  36 };
  37
  38 static int da9055_gpio_get(struct gpio_chip *gc, unsigned offset)
  39 {
  40         struct da9055_gpio *gpio = gpiochip_get_data(gc);
  41         int gpio_direction = 0;
  42         int ret;
  43
  44         /* Get GPIO direction */
  45         ret = da9055_reg_read(gpio->da9055, (offset >> 1) + DA9055_REG_GPIO0_1);
  46         if (ret < 0)
  47                 return ret;
  48
  49         gpio_direction = ret & (DA9055_PORT_MASK) << DA9055_PORT_SHIFT(offset);
  50         gpio_direction >>= DA9055_PORT_SHIFT(offset);
  51         switch (gpio_direction) {
  52         case DA9055_INPUT:
  53                 ret = da9055_reg_read(gpio->da9055, DA9055_REG_STATUS_B);
  54                 if (ret < 0)
  55                         return ret;
  56                 break;
  57         case DA9055_OUTPUT:
  58                 ret = da9055_reg_read(gpio->da9055, DA9055_REG_GPIO_MODE0_2);
  59                 if (ret < 0)
  60                         return ret;
  61         }
  62
  63         return ret & (1 << offset);
  64
  65 }
  66
  67 static void da9055_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
  68 {
  69         struct da9055_gpio *gpio = gpiochip_get_data(gc);
  70
  71         da9055_reg_update(gpio->da9055,
  72                         DA9055_REG_GPIO_MODE0_2,
  73                         1 << offset,
  74                         value << offset);
  75 }
  76
  77 static int da9055_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
  78 {
  79         struct da9055_gpio *gpio = gpiochip_get_data(gc);
  80         unsigned char reg_byte;
  81
  82         reg_byte = (DA9055_ACT_LOW | DA9055_GPI)
  83                                 << DA9055_PORT_SHIFT(offset);
  84
  85         return da9055_reg_update(gpio->da9055, (offset >> 1) +
  86                                 DA9055_REG_GPIO0_1,
  87                                 DA9055_PORT_MASK <<
  88                                 DA9055_PORT_SHIFT(offset),
  89                                 reg_byte);
  90 }
  91
  92 static int da9055_gpio_direction_output(struct gpio_chip *gc,
  93                                         unsigned offset, int value)
  94 {
  95         struct da9055_gpio *gpio = gpiochip_get_data(gc);
  96         unsigned char reg_byte;
  97         int ret;
  98
  99         reg_byte = (DA9055_VDD_IO | DA9055_PUSH_PULL)
 100                                         << DA9055_PORT_SHIFT(offset);
 101
 102         ret = da9055_reg_update(gpio->da9055, (offset >> 1) +
 103                                 DA9055_REG_GPIO0_1,
 104                                 DA9055_PORT_MASK <<
 105                                 DA9055_PORT_SHIFT(offset),
 106                                 reg_byte);
 107         if (ret < 0)
 108                 return ret;
 109
 110         da9055_gpio_set(gc, offset, value);
 111
 112         return 0;
 113 }
 114
 115 static int da9055_gpio_to_irq(struct gpio_chip *gc, u32 offset)
 116 {
 117         struct da9055_gpio *gpio = gpiochip_get_data(gc);
 118         struct da9055 *da9055 = gpio->da9055;
 119
 120         return regmap_irq_get_virq(da9055->irq_data,
 121                                   DA9055_IRQ_GPI0 + offset);
 122 }
 123
 124 static const struct gpio_chip reference_gp = {
 125         .label = "da9055-gpio",
 126         .owner = THIS_MODULE,
 127         .get = da9055_gpio_get,
 128         .set = da9055_gpio_set,
 129         .direction_input = da9055_gpio_direction_input,
 130         .direction_output = da9055_gpio_direction_output,
 131         .to_irq = da9055_gpio_to_irq,
 132         .can_sleep = true,
 133         .ngpio = 3,
 134         .base = -1,
 135 };
 136
 137 static int da9055_gpio_probe(struct platform_device *pdev)
 138 {
 139         struct da9055_gpio *gpio;
 140         struct da9055_pdata *pdata;
 141         int ret;
 142
 143         gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
 144         if (!gpio)
 145                 return -ENOMEM;
 146
 147         gpio->da9055 = dev_get_drvdata(pdev->dev.parent);
 148         pdata = dev_get_platdata(gpio->da9055->dev);
 149
 150         gpio->gp = reference_gp;
 151         if (pdata && pdata->gpio_base)
 152                 gpio->gp.base = pdata->gpio_base;
 153
 154         ret = devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio);
 155         if (ret < 0) {
 156                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 157                 return ret;
 158         }
 159
 160         platform_set_drvdata(pdev, gpio);
 161
 162         return 0;
 163 }
 164
 165 static struct platform_driver da9055_gpio_driver = {
 166         .probe = da9055_gpio_probe,
 167         .driver = {
 168                 .name   = "da9055-gpio",
 169         },
 170 };
 171
 172 static int __init da9055_gpio_init(void)
 173 {
 174         return platform_driver_register(&da9055_gpio_driver);
 175 }
 176 subsys_initcall(da9055_gpio_init);
 177
 178 static void __exit da9055_gpio_exit(void)
 179 {
 180         platform_driver_unregister(&da9055_gpio_driver);
 181 }
 182 module_exit(da9055_gpio_exit);
 183
 184 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 185 MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
 186 MODULE_LICENSE("GPL");
 187 MODULE_ALIAS("platform:da9055-gpio");